The advertising watchdog has banned a TV campaign run by the Sun after complaints that it "directly exhorted" children to buy the paper.

The campaign featured former footballer and TV pundit Ian Wright discussing a Sun football trading card promotion, called Topps Match Attax, with a group of children. One of the children asked if any of the players featured on the cards were "worth a week's pocket money", while another said that the promotion was "giving away the new season".

The Advertising Standards Authority challenged whether the ad "directly exhorted" children to buy the Sun or encouraged them to ask other people to buy it for them in order to get hold of the trading cards.

News Group Newspapers, the Sun's publisher, denied the accusations and said that references to money in the ad were a "humorous juxtaposition" between a children's football game and the "escalating prices in the English transfer market". The use of children was a "comedic device" aimed at adults, the company said.

The ASA said the use of the phrase "pocket money" as a joke about Premier League footballers' pay was "subtle".

"[The joke] might be lost on some young viewers, who would instead understand the claim to mean it was worth buying the Sun with their pocket money in order to get the Match Attax cards, particularly because the line was said by a child," the ASA said, adding that the use of Wright meant that the commercial was "likely to be seen to directly target children".

"Because we considered some young viewers would understand the reference to pocket money as an encouragement to purchase, we considered the ad directly exhorted children to buy the Sun to obtain the promotional football cards," the ASA said.

It banned the ad for breaking rules on marketing to children.

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